1. Field of the Invention
The present invention relates to a device and method for refilling an ink cartridge and more particularly to a device and method for refilling an ink cartridge that contains therein an ink absorbing material such as sponge.
2. Prior Art
Various types of ink cartridges that are used in computer printers are manufactured and marketed. One type of ink cartridge has an ink reservoir tank to store ink therein, and another type of ink cartridge includes an ink absorbing material such as a sponge inside to store ink. When this type of ink cartridge is refilled, ink is dropped onto the ink absorbing material so as to let the ink permeate the ink absorbing material. Another way to refill this type of ink cartridge is to introduce a pipe into the cartridge so that the pipe penetrates into the sponge and then ink is introduced into the pipe from an ink supply pack, thus allowing the ink to flow down the pipe and to be absorbed by the ink absorbing material.
When the cartridge is refilled by way of letting the ink drop onto the ink absorbing material, the ink first drops on the surface of the ink absorbing material and then gradually permeates downward so as to be absorbed and stored in the ink absorbing material. However, different cartridges use different types of ink absorbing materials which have various characteristics. In addition, even in the cartridges that have the same ink absorbing material, the absorbing efficiency of the ink differs depending upon the condition of the ink absorbing material due to the ambient and inside temperatures, period of use of the cartridges, etc. Occasionally, the refilling ink overflows and comes out of the ink filling aperture of the cartridge even before the cartridge is fully refilled.
When the cartridge is refilled via a pipe that is brought into contact with the ink absorbing material inside the cartridge, a hazard of overflowing is less likely to occur; however, since the ink outlet of the pipe is in direct contact with the ink absorbing material, the ink absorbing material tends to hinder a smooth outflow of the ink, thus allowing the refilling ink to fill up the pipe. So as to avoid this, syringes are often used in order to forcefully transfer the ink into the ink cartridge. However, the flow of the ink by a syringe receives a resistance from the ink absorbing material; and as a result, the ink refill process requires a greater force to push the ink out of the syringe. In addition, the speed of the ink being forced out of the pipe can vary depending upon the resistance from the ink absorbing material; and, it is always necessary to apply an appropriate force to force out the ink from the syringe for each one of the different cartridges to be refilled.